MUMBAI, Feb 6 (Reuters) - Gold demand in India is likely to remain below its 10-year average for a third year in 2018 as higher taxes and new transparency rules on purchases may cap last year's rebound in buying, the World Gold Council (WGC) said on Tuesday.

India is the world's second-biggest gold consumer and lower demand there could rein in global prices that have risen 8 percent since the middle of December, although a drop in gold imports would help India reduce its trade deficit.

Gold consumption in 2018 will likely be between 700 and 800 tonnes versus 727 tonnes last year, Somasundaram PR, the managing director of WGC's Indian operations, said on Tuesday. Indian demand averaged 840 tonnes over the last 10 years.

Gold demand will lag because of the higher goods and services tax (GST) on bullion purchases imposed in 2017 and measures to track gold purchases, he said.

In July, the GST on gold was raised to 3 percent from 1.2 percent. India has also made it mandatory for customers to disclose their tax code, or Permanent Account Number (PAN), for high-value gold purchases.

The government moves have disrupted the business of the small jewellers that account for nearly two-thirds of India's total sales, Somasundaram said.

"More changes are coming in like hall marking, responsible gold sourcing, all this will continue to disrupt the industry... It will take two years for India to reach normal demand level," he said.

Gold is a mainstay of Indian culture, serving as the primary vehicle for household savings for hundreds of millions of people in Asia's third-largest economy.

Gold demand in the country rose 9 percent in 2017 from 2016 to 726.9 tonnes as jewellery demand rose 12 percent from a year ago, the WGC said in a report published on Tuesday.